Answer: Mold is not a good thing to have on seed starting soil. It indicates that there has been too much moisture or humidity during or after the seeds germinated. It can affect your seedlings so take immediate steps to increase air circulation and reduce the relative humidity near the plants. The clear plastic cover that came with your kit should have been placed over the tray until the seeds germinated and then removed to allow for good air circulation. Your plants may be okay, but they may also succumb to damping-off fungus. Time will tell. Next time you start seeds, be sure to remove the cover after they've germinated to provide good air circulation.
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